CN120812645A

CN120812645A - Method, device, equipment, storage medium and program product for determining delay compensation value

Info

Publication number: CN120812645A
Application number: CN202511281521.3A
Authority: CN
Inventors: 刘伟利; 吕磊; 向泽宇; 柏浩钧
Original assignee: Sichuan Innogence Technology Co Ltd
Current assignee: Sichuan Innogence Technology Co Ltd
Priority date: 2025-09-09
Filing date: 2025-09-09
Publication date: 2025-10-17

Abstract

The present application provides a method, apparatus, device, storage medium, and program product for determining a delay compensation value, relating to the field of communication technology. This method effectively overcomes the delay estimation inaccuracy caused by model errors and orbital perturbations in traditional static ephemeris prediction methods by introducing a dynamic error compensation mechanism driven by historical ephemeris data. By calculating the historical average delay error similar to the current scenario, the delay deviation at the current moment can be more accurately estimated, thereby significantly reducing the risk of "negative delay" caused by overcompensation and improving the transmission reliability of the satellite uplink and the receiver demodulation success rate.

Description

Method, device, equipment, storage medium and program product for determining delay compensation value

Technical Field

The present application relates to the field of communications technologies, and in particular, to a method, an apparatus, a device, a storage medium, and a program product for determining a delay compensation value.

Background

In the field of satellite communications, and in particular low earth orbit satellite communications systems, dynamic latency of signal transmission is one of the core challenges affecting communications reliability. In order to ensure that signals can be correctly received within a predetermined receiving window of a satellite, a static time delay precompensation method based on ephemeris prediction is commonly adopted in the prior art.

The technical principle of the scheme is that a ground terminal receives satellite orbit ephemeris data periodically issued by a satellite base station. These ephemeris data typically contain information such as the position, velocity, and time stamp of the satellites. Based on this information, the terminal extrapolates the predicted accurate position of the satellite over a period of time in the future using classical satellite orbit dynamics models (e.g., kepler orbit equations and perturbation models thereof). And then, calculating the theoretical satellite-ground distance of signal transmission according to the predicted satellite position and the geographic position of the terminal, and further estimating the satellite-ground transmission delay. And finally, the terminal adjusts the sending time of the data according to the time delay estimated value so as to compensate the transmission delay, and the signal accurately reaches the satellite.

The actual orbit of a satellite is affected by various complex spatial dynamics such as atmospheric drag, solar pressure, earth's non-spherical gravitational fields, etc. These factors are difficult to model and predict with complete accuracy in the kinetic model. Especially for satellites with low orbit heights, the influence of the perturbation is more pronounced, leading to unavoidable deviations between the predicted position based on model extrapolation and the actual real position. This orbit prediction error is directly translated into a delay estimation error.

The most serious consequence of the above-mentioned errors and lack of dynamics is the possibility of causing overcompensation. When the delay predicted value of the terminal is greater than the actual delay due to the orbit prediction deviation, the terminal can excessively transmit the signal in advance. This results in the signal arriving before the satellite receiver is ready (i.e. before the expected receive window is opened), creating a negative relative delay on the time axis of the receiver. For systems employing orthogonal frequency division multiplexing (Orthogonal Frequency Division Multiplexing, OFDM) and other technologies, negative delay can destroy symbol timing synchronization, cause Cyclic Prefix (CP) failure, introduce serious inter-carrier interference and inter-symbol interference, and finally cause demodulation failure and communication link interruption.

Disclosure of Invention

An object of the embodiments of the present application is to provide a method, apparatus, device, storage medium and program product for determining a delay compensation value, so as to solve the problem in the prior art that a terminal estimates delay based on predicted ephemeris data, resulting in a large delay error, and further affecting communication quality.

In a first aspect, an embodiment of the present application provides a method for determining a delay compensation value, which is applied to a terminal, where the method includes:

Acquiring current actual ephemeris data issued by a satellite base station;

Determining a plurality of historical actual ephemeris data similar to the current actual ephemeris data and a plurality of historical prediction ephemeris data corresponding to the plurality of historical actual ephemeris data, wherein the plurality of historical actual ephemeris data are identical to the plurality of historical prediction ephemeris data in corresponding time, and the historical prediction ephemeris data are obtained by prediction based on the historical actual ephemeris data;

calculating an average delay error between the plurality of historical actual ephemeris data and the plurality of historical predicted ephemeris data;

And determining a delay compensation value according to the average delay error.

In the implementation process, the problem of inaccurate time delay estimation caused by model errors and orbit perturbation in the traditional static ephemeris prediction method is effectively solved by introducing a dynamic error compensation mechanism driven by historical ephemeris data, and the time delay deviation at the current moment can be estimated more accurately by calculating the historical average time delay error similar to the current scene, so that the risk of negative time delay caused by over compensation is obviously reduced, and the transmission reliability of a satellite uplink and the demodulation success rate of a receiver are improved.

Optionally, the determining a plurality of historical actual ephemeris data similar to the current actual ephemeris data and a plurality of historical predicted ephemeris data corresponding to the plurality of historical actual ephemeris data includes:

Acquiring stored actual ephemeris data and predicted ephemeris data of the satellite base station in each of a plurality of satellite orbit operation periods;

and screening a plurality of historical actual ephemeris data similar to the current actual ephemeris data from the actual ephemeris data of each satellite orbit operation period, and acquiring historical predicted ephemeris data with the same time as the plurality of historical actual ephemeris data from the predicted ephemeris data of the corresponding satellite orbit operation period.

In the implementation process, due to long-term perturbation drift of the satellite orbit, systematic deviation exists in orbit trajectories of different operation periods. According to the scheme, the data are screened through the separate operation periods, the historical ephemeris data section which is most similar to the current space-time position is screened from each historical satellite orbit operation period by utilizing the inherent periodicity and space-time correlation of satellite operation, so that the fact that the referenced historical data are highly similar to the orbit drift state of the current satellite is ensured, the time delay error characteristic under the current orbit position can be captured more accurately, the correlation and reference value of the historical data and the current scene are effectively improved through the screening mechanism based on the space-time similarity, the time delay error characteristic under the current orbit perturbation state is captured more accurately, the accuracy and the robustness of time delay error estimation are obviously enhanced, and a more reliable data basis is provided for the follow-up dynamic time delay compensation.

Optionally, the screening the plurality of historical actual ephemeris data similar to the current actual ephemeris data from the actual ephemeris data of each satellite orbit period includes:

And screening a plurality of historical actual ephemeris data with the distance from the current actual ephemeris data smaller than a set threshold value from the actual ephemeris data of each satellite orbit operation period.

In the implementation process, the historical actual ephemeris data with the distance smaller than the threshold value from the current actual ephemeris data can be accurately positioned by setting the threshold value to screen the historical actual ephemeris data with the distance smaller than the threshold value from the current actual ephemeris data. The method effectively reduces the data screening range, improves the data processing efficiency, and enhances the accuracy of time delay compensation. By focusing on historical data similar to the current state, delay errors can be more accurately predicted and compensated.

screening target actual ephemeris data with the minimum distance from the current actual ephemeris data from the actual ephemeris data of each satellite orbit operation period;

And acquiring a plurality of historical actual ephemeris data in a set time period including the moment corresponding to the target actual ephemeris data in each satellite orbit operation period.

In the implementation process, the target actual ephemeris data with the smallest distance with the current actual ephemeris data is selected through screening, and a plurality of historical actual ephemeris data in a set time period before and after the moment corresponding to the target data are further obtained, so that the dynamic change characteristics of the satellite orbit can be captured more accurately. The method not only ensures the high similarity of the screened historical data and the current data, but also provides more abundant context information through the expansion of the time period, and is helpful for more comprehensively evaluating the delay error. This makes the delay compensation more accurate.

Optionally, the calculating an average delay error between the plurality of historical actual ephemeris data and the plurality of historical predicted ephemeris data comprises:

and determining an average delay error corresponding to each satellite orbit operation period according to the delay errors between the plurality of historical actual ephemeris data and the plurality of historical prediction ephemeris data in each satellite orbit operation period.

In the implementation process, the average delay error corresponding to each satellite orbit operation period is determined by calculating the delay errors between a plurality of historical actual ephemeris data and a plurality of historical predicted ephemeris data in each satellite orbit operation period. The method can analyze the time delay change condition in each satellite orbit running period more carefully, thereby providing more accurate time delay compensation basis.

Optionally, the determining a delay compensation value according to the average delay error includes:

determining a delay error corresponding to each satellite orbit operation period according to the average delay error corresponding to each satellite orbit operation period and the delay fluctuation quantity of the delay error between a plurality of historical actual ephemeris data and a plurality of historical prediction ephemeris data in each satellite orbit operation period;

and determining a time delay compensation value according to the time delay error corresponding to each satellite orbit operation period.

In the implementation process, the key index of the time delay fluctuation quantity, which is used for measuring the fluctuation degree of the data, can be introduced to effectively capture the fluctuation and uncertainty of the time delay error, so that a conservative estimated value containing a safety boundary is constructed on the basis of the average error, the calculation mode of combining the average value and the time delay fluctuation quantity effectively avoids the unilateral property of the average value, the negative time delay or intersymbol interference risk caused by extreme error values (such as overlarge positive error or negative error) can be obviously reduced, and the robustness of the time delay compensation value and the communication reliability of the system in a dynamic change channel are greatly improved.

Optionally, the delay fluctuation amount is determined based on a standard deviation of delay errors between a plurality of historical actual ephemeris data and a plurality of historical predicted ephemeris data in each satellite orbit period and the adjustment coefficient k.

In the implementation process, the delay fluctuation amount based on the standard deviation is introduced, and the essence is to construct a dynamic and statistically safe boundary (confidence upper boundary) for the delay compensation value. The occurrence probability of negative time delay (namely, the signal arrives in advance) can be controlled at an extremely low level by adjusting the coefficient k, so that the system can flexibly adjust the conservation degree of the safety boundary, the reliability of the communication link is preferentially ensured, and the risk of demodulation failure caused by extreme prediction errors is effectively controlled.

Optionally, the determining the delay compensation value according to the delay error corresponding to each satellite orbit running period includes:

and carrying out weighted summation on the time delay errors corresponding to each satellite orbit operation period to obtain a time delay compensation value.

In the implementation process, the delay compensation value is determined by carrying out weighted summation on the delay errors corresponding to each satellite orbit operation period, and the method can comprehensively consider the delay error characteristics of different satellite orbit operation periods and endow each period with different weights, so that the overall delay error condition is reflected more accurately.

Optionally, after determining the delay compensation value according to the average delay error, the method further includes:

Receiving TA adjustment quantity issued by the satellite base station;

And correcting the TA adjustment amount according to the time delay compensation value adopted at the last data transmission moment to obtain the corrected TA adjustment amount.

In the implementation process, the accuracy of the TA adjustment amount can be further optimized by receiving the TA adjustment amount issued by the satellite base station and correcting the TA adjustment amount according to the time delay compensation value adopted at the last data transmission time. The method not only considers the influence of ephemeris prediction error on time delay, but also dynamically corrects the TA adjustment amount through the time delay compensation value, thereby more accurately adjusting the sending time or the receiving window.

Optionally, the correcting the TA adjustment according to the delay compensation value adopted at the last data transmission time to obtain a corrected TA adjustment includes:

if the TA adjustment amount is larger than the time delay compensation value adopted at the last data transmission time, subtracting the time delay compensation value adopted at the last data transmission time from the TA adjustment amount to obtain a corrected TA adjustment amount;

And if the TA adjustment amount is smaller than or equal to the time delay compensation value adopted at the last data transmission time, setting the TA adjustment amount to 0 to obtain the corrected TA adjustment amount.

In the implementation process, the delay compensation value adopted at the last data transmission moment is used as a dynamic safety threshold value to intelligently correct the original TA adjustment quantity issued by the base station, the rule can radically stop the phenomenon of excessive compensation, when the TA adjustment quantity is too large, the potential risk is eliminated by subtracting the compensation value, and when the TA adjustment quantity is lower than the safety threshold value, the most conservative zero-setting strategy is adopted to preferentially ensure that the signal does not arrive in advance, thereby reducing the demodulation failure problem caused by negative delay as much as possible. This is equivalent to adding a "safety valve" before executing the base station instruction, ensuring that the final transmit time adjustment does not break through the locally calculated safety boundary, thereby realizing compliance with network control and maximally guaranteeing the reliability of the link.

Optionally, after the corrected TA adjustment amount is obtained, the method further includes:

Determining the data transmission time advance of the terminal according to the corrected TA adjustment amount, a satellite-to-ground delay value determined based on the predicted ephemeris data at the data transmission time and the delay compensation value;

And transmitting data according to the data transmission time advance.

In the implementation process, the corrected TA adjustment amount, the predicted satellite-ground time delay based on the predicted ephemeris and the time delay compensation value are cooperatively calculated to finally generate an optimal transmission time advance which is fused with a base station instruction, local prediction and historical error intelligent evaluation, and the decision mechanism of multi-source information fusion realizes dynamic fine adjustment of the transmission time, so that the coarse adjustment instruction and the local prediction information of the base station are fully utilized, and the safety calibration is carried out on the coarse adjustment instruction and the local prediction information through the historical error compensation value, thereby maximally ensuring that signals arrive in an ideal receiving window in a complex dynamic satellite channel, and simultaneously reducing the negative time delay risk as much as possible.

In a second aspect, an embodiment of the present application provides a delay compensation value determining apparatus, applied to a terminal, where the apparatus includes:

the data acquisition module is used for acquiring current actual ephemeris data issued by the satellite base station;

The data searching module is used for determining a plurality of historical actual ephemeris data similar to the current actual ephemeris data and a plurality of historical prediction ephemeris data corresponding to the historical actual ephemeris data, wherein the historical prediction ephemeris data are obtained by prediction based on the historical actual ephemeris data, and the time corresponding to the historical prediction ephemeris data is the same;

a delay error calculation module, configured to calculate an average delay error between the plurality of historical actual ephemeris data and the plurality of historical predicted ephemeris data;

and the delay compensation module is used for determining a delay compensation value according to the average delay error.

In a third aspect, an embodiment of the present application provides an electronic device comprising a processor and a memory storing computer readable instructions which, when executed by the processor, perform the steps of the method as provided in the first aspect above.

In a fourth aspect, embodiments of the present application provide a computer readable storage medium having stored thereon a computer program which when executed by a processor performs the steps of the method as provided in the first aspect above.

In a fifth aspect, embodiments of the present application provide a computer program product comprising computer program instructions which, when read and run by a processor, perform the steps of the method as provided in the first aspect above.

Additional features and advantages of the application will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the embodiments of the application. The objectives and other advantages of the application will be realized and attained by the structure particularly pointed out in the written description and claims thereof as well as the appended drawings.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the embodiments of the present application will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present application and should not be considered as limiting the scope, and other related drawings can be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic diagram of a system architecture to which the scheme of the present application is applied according to an embodiment of the present application;

fig. 2 is a flowchart of a method for determining a delay compensation value according to an embodiment of the present application;

fig. 3 is a schematic diagram of a timing representation of determining a delay compensation value by a terminal under various conditions according to an embodiment of the present application;

Fig. 4 is a block diagram of a delay compensation value determining apparatus according to an embodiment of the present application;

Fig. 5 is a schematic structural diagram of an electronic device for executing a method for determining a delay compensation value according to an embodiment of the present application.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application.

It should be noted that the terms "system" and "network" in embodiments of the present invention may be used interchangeably. "plurality" means two or more, and "plurality" may also be understood as "at least two" in this embodiment of the present invention. "and/or" describes an association relationship of an association object, and indicates that there may be three relationships, for example, a and/or B, and may indicate that there are three cases of a alone, a and B together, and B alone. The character "/", unless otherwise specified, generally indicates that the associated object is an "or" relationship.

It should be further noted that, in the present application, all actions of acquiring signals, information or data are performed under the condition of conforming to the corresponding data protection rule policy of the country of the location and obtaining the authorization given by the owner of the corresponding device.

The technical scheme of the application can be applied to Non-ground network (Non-TERRESTRIAL NETWORK, NTN) systems such as satellite communication systems, high altitude platform (high altitude platform station, HAPS) communication and the like, for example, communication and navigation integrated (INTEGRATED COMMUNICATION AND NAVIGATION, ICaN) systems, global navigation satellite systems (global navigation SATELLITE SYSTEM, GNSS) and the like.

The satellite communication system may be integrated with a conventional mobile communication system. For example, the mobile communication system may be a fourth generation (4th generation,4G) communication system (e.g., long term evolution (long term evolution, LTE) system), a worldwide interoperability for microwave access (worldwide interoperability formicrowave access, wiMAX) communication system, a fifth generation (5th generation,5G) communication system (e.g., new radio, NR) system), a future mobile communication system, and the like.

The system architecture or scenario in which the present application is mainly applied is shown in fig. 1, and includes a base station and a terminal. The base station may refer to a satellite base station in a satellite system. The satellite base station in the embodiment of the application can also be a satellite or network side equipment carried on the satellite.

Satellite communication systems can be classified into three types, a geostationary orbit (geostationary earth orbit, GEO) satellite communication system, also known as a geostationary orbit satellite communication system, a medium earth orbit (medium earth orbit, MEO) satellite communication system, and a Low Earth Orbit (LEO) satellite communication system, according to the orbital heights of the satellites. The GEO satellite orbit has a altitude of 35786km, which has the main advantages of keeping stationary relative to the ground and providing a large coverage area. However, GEO satellite communication also has the obvious defects that the GEO satellite orbit is far away from the earth, free space propagation loss is large, communication link budget is tense, in order to increase transmission or receiving gain, a large-caliber antenna is required to be arranged for the satellite, the GEO communication transmission delay is large, the round trip delay can reach about 500ms, the requirement of low-delay service cannot be met, the GEO orbit resource is relatively tense, the transmission cost is high, and coverage cannot be provided for the earth two-pole region. The orbit height of the MEO satellite is positioned in the range of 2000-356 km, and the method has the advantages that the global coverage can be realized through relatively less satellite numbers, but the orbit height is higher than LEO, and compared with LEO satellite communication transmission delay, the method is still larger. The orbit height of the LEO satellite is 300-2000 km, and the LEO satellite is lower than the MEO orbit height and the GEO orbit height, and has the advantages of smaller data propagation delay, small transmission loss and low transmitting cost. Of course, in some specific application scenarios, LEO satellites may be replaced by GEO satellites or MEO satellites, or even a combination of multiple types of satellites.

The terminal mentioned in the embodiments of the present application includes various handheld devices, vehicle apparatuses, wearable apparatuses, computing apparatuses or other processing apparatuses connected to a wireless modem, and may specifically refer to a User Equipment (UE), an access terminal, a subscriber unit, a subscriber station, a mobile station, a remote terminal, a mobile apparatus, a user terminal, a wireless communication apparatus, a user agent or a user device. The terminal may also be a satellite phone, a cellular phone, a smart phone, a wireless data card, a wireless modem, a machine type communication device, a cordless phone, a session initiation protocol (session initiation protocol, SIP) phone, a wireless local loop (wireless local loop, WLL) station, a personal digital assistant (personal DIGITAL ASSISTANT, PDA), a handheld device with wireless communication functionality, a computing device or other processing device connected to a wireless modem, a car mounted device or a wearable device, a Virtual Reality (VR) terminal device, an augmented reality (augmented reality, AR) terminal device, a wireless terminal in industrial control (industrial control), a wireless terminal in unmanned (SELF DRIVING), a wireless terminal in telemedicine (remote medium), a wireless terminal in smart grid (SMART GRID), a wireless terminal in transportation security (transportation safety), a wireless terminal in smart city (SMART CITY), a wireless terminal in smart home (smart home), a terminal in a 5G network or a future communication network, etc.

The embodiment of the application provides a delay compensation value determining method which is applied to a terminal, effectively solves the problem of inaccurate delay estimation caused by model errors and orbit perturbation in the traditional static ephemeris prediction method by introducing a dynamic error compensation mechanism driven by historical ephemeris data, and can more accurately estimate the delay deviation at the current moment by calculating the historical average delay error similar to the current scene, thereby obviously reducing the risk of negative delay caused by excessive compensation and improving the transmission reliability of a satellite uplink and the demodulation success rate of a receiver.

Example 1

Referring to fig. 2, fig. 2 is a flowchart of a method for determining a delay compensation value according to an embodiment of the present application, where the method includes the following steps:

step S110, current actual ephemeris data issued by the satellite base station is obtained.

On the satellite base station side, the satellite base station can periodically or aperiodically acquire actual ephemeris data from the ephemeris platform at intervals, and a signaling is newly added, and the actual ephemeris data acquired from the ephemeris platform is sent to the terminal through the signaling.

Synchronously, the satellite base station is provided with an ephemeris data transmitting period, and the transmitted ephemeris data refers to predicted ephemeris data obtained by prediction based on actual ephemeris data.

For example, after the satellite base station obtains the actual ephemeris data from the ephemeris platform at time t1, the actual ephemeris data is sent to the terminal through signaling, and when the time of sending the predicted ephemeris data of the satellite base station is at time t2, the satellite base station predicts based on the actual ephemeris data obtained at time t1 to obtain the predicted ephemeris data at time t2 (here, the prediction may be implemented through a correlation algorithm, for example, a neural network model (such as CNN (Convolutional Neural Network, convolutional neural network), LSTM (Long Short-Term Memory network), or Long-Term Memory network)), or an orbit dynamics model, and sends the predicted ephemeris data to the terminal at time t 2. That is, the satellite base station may issue two kinds of ephemeris data to the terminal, one is actual ephemeris data obtained from the ephemeris platform, and the other is predicted ephemeris data obtained by predicting based on the actual ephemeris data, where the time and/or period of issuing the two kinds of ephemeris data may be different.

The ephemeris data may include information such as orbit parameters, time stamps, etc. of the satellite base station.

In some embodiments, in order to facilitate the terminal to distinguish between the two types of ephemeris data, when the satellite base station issues the ephemeris data, the satellite base station may carry a corresponding identifier in the ephemeris data, for example, identifier 0 represents the actual ephemeris data, and identifier 1 represents the predicted ephemeris data. In this way, after the terminal acquires the ephemeris data, the type of the ephemeris data, that is, whether the actual ephemeris data or the predicted ephemeris data, can be determined according to the identifier, and in order to facilitate subsequent processing, the terminal may store two types of ephemeris data in different caches, for example, the actual ephemeris data is stored in the first cache, the predicted ephemeris data is stored in the second cache, and when the ephemeris data is stored, the receiving time corresponding to each ephemeris data may be synchronously stored.

In some embodiments, the common terminal adjusts the data transmission time with reference to TA (Timing Advance) adjustment amounts issued by the satellite base station. However, in some cases, the satellite base station may close the control of the TA adjustment, that is, in this case, the satellite base station does not issue the TA adjustment or issues the TA adjustment for a long period, so that the terminal may adjust the data transmission time according to the satellite-to-ground delay value estimated by itself. Therefore, in this embodiment, the triggering condition for determining the delay compensation value by the terminal may be that after receiving the actual ephemeris data, that is, after the terminal receives one piece of actual ephemeris data issued by the satellite base station, the delay compensation value is determined by the scheme, and then the sending time of the data is adjusted by combining the satellite-to-ground delay value estimated by the terminal.

Step S120, determining a plurality of historical actual ephemeris data similar to the current actual ephemeris data and a plurality of historical predicted ephemeris data corresponding to the plurality of historical actual ephemeris data.

The time points of the plurality of historical actual ephemeris data and the plurality of historical predicted ephemeris data are the same, and the historical predicted ephemeris data are predicted based on the historical actual ephemeris data.

The terminal stores actual ephemeris data and predicted ephemeris data issued by the satellite base station, and the first buffer stores the actual ephemeris data, and the second buffer stores the predicted ephemeris data. Since the actual ephemeris data and the predicted ephemeris data are delivered in different periods or times. In some embodiments, the terminal may predict one ephemeris data according to its own requirement, for example, when the terminal adjusts the sending time of the uplink data, the terminal needs to adjust the predicted ephemeris delay value and the time offset value according to the ephemeris data. In this case, after the terminal may receive the actual ephemeris data or the predicted ephemeris data (for convenience of distinction, referred to herein as first predicted ephemeris data), the terminal may predict the ephemeris data at the time of data transmission (referred to herein as second predicted ephemeris data), where the predicted ephemeris data at the time of data transmission may be the actual ephemeris data or the predicted ephemeris data according to the ephemeris data recently issued by the satellite base station, and both the first predicted ephemeris data and the second predicted ephemeris data may be stored in the second buffer.

In practical application, the period of the actual ephemeris data issued by the satellite base station is larger than the period of the predicted ephemeris data issued by the satellite base station, so that the time of the actual ephemeris data can be aligned with the time of the predicted ephemeris data in principle.

After obtaining the current actual ephemeris data, the terminal may search for a plurality of historical actual ephemeris data similar to the current actual ephemeris data from the stored actual ephemeris data (i.e. the first buffer), then determine the time of the plurality of historical actual ephemeris data, and search for the historical predicted ephemeris data at the same time from the stored predicted ephemeris data (i.e. the second buffer) based on the time, where the searched historical predicted ephemeris data may include the first predicted ephemeris data and the second predicted ephemeris data, and since the first predicted ephemeris data is predicted by the satellite base station based on the actual ephemeris data, the second predicted ephemeris data is predicted by the terminal based on the actual ephemeris data or the first predicted ephemeris data (the predicted ephemeris data is predicted by the satellite base station based on the actual ephemeris data), the historical predicted ephemeris data is predicted based on the historical actual ephemeris data in principle.

It will be appreciated that if N pieces of history actual ephemeris data similar to the current actual ephemeris data are determined, N pieces of history prediction ephemeris data may be obtained from the second buffer, and of course, less than N pieces of history prediction ephemeris data (for example, M pieces of history prediction ephemeris data, M being less than N) may be obtained, if M pieces of history prediction ephemeris data are obtained, in the case of subsequent processing, the N pieces of history actual ephemeris data and the M pieces of history prediction ephemeris data are deleted from the non-upper history actual ephemeris data, and M pieces of history actual ephemeris data are left, where M pieces of history actual ephemeris data and M pieces of history prediction ephemeris data are in one-to-one correspondence, that is, each of M pieces of time corresponds to one history actual ephemeris data and history prediction ephemeris data.

The similarity is understood to be historical actual ephemeris data with high similarity with the current actual ephemeris data, for example, the similarity can be determined by calculating the euclidean distance, cosine distance and the like between the current actual ephemeris data and the historical actual ephemeris data, then the historical actual ephemeris data with the similarity higher than a set threshold value is screened out, and the historical predicted ephemeris data at the corresponding moment is obtained.

Step S130, calculating average time delay errors between the plurality of historical actual ephemeris data and the plurality of historical predicted ephemeris data.

In some embodiments, after obtaining each actual ephemeris data, the terminal may estimate an earth time delay value based on the actual ephemeris data, where the time delay may be stored in the first buffer, that is, the first buffer stores a corresponding relationship between the actual ephemeris data and the time+earth time delay value, and after obtaining each predicted ephemeris data (including the first predicted ephemeris data and the second predicted ephemeris data), estimate an earth time delay value based on the predicted ephemeris data, where the time delay may be stored in the second buffer, and the second buffer stores a corresponding relationship between the predicted ephemeris data and the time+earth time delay value.

The terminal can determine the position of the satellite base station from the ephemeris data, and can calculate the distance between the satellite base station and the satellite base station by combining the position of the terminal, and the time delay can be obtained by dividing the distance by the speed of light. Of course, ephemeris data, position information of the terminal, environmental information of the terminal (the environmental information can be acquired by a related sensor on the terminal), and the like can also be input into the neural network model for time delay prediction, so that satellite-to-ground time delay values can be obtained.

In this way, the terminal can obtain the satellite-to-ground delay value corresponding to each actual ephemeris data in the plurality of historical actual ephemeris data from the first buffer memory, obtain the satellite-to-ground delay value corresponding to each predicted ephemeris data in the plurality of historical predicted ephemeris data from the second buffer memory, and then the difference value of the two satellite-to-ground delay values is the delay error.

For example, when the time T1 corresponds to the historical actual ephemeris data x1 and the historical predicted ephemeris data x2, the satellite-to-ground delay value corresponding to x1 is T1, and the satellite-to-ground delay value corresponding to x2 is T2, the delay error corresponding to the two ephemeris data is T1-T2, so that the delay error between the two ephemeris data corresponding to each time can be obtained.

In some other embodiments, the time delay error between the historical actual ephemeris data and the historical predicted ephemeris data corresponding to each time instant is calculated, and may also be obtained by calculating the distance between the two ephemeris data. For example, the distance D1 between the position of the satellite base station and the position of the terminal in x1 at time t1 and the distance D2 between the position of the satellite base station and the position of the terminal in x2 at time t1 are calculated, and then the delay error is obtained by dividing the distance difference (D1-D2) by the speed of light.

And then, carrying out average calculation (a moving average filtering algorithm, a Kalman filtering algorithm and the like can be adopted) on the delay errors corresponding to the moments (such as M moments), so that the average delay error can be obtained.

And step 140, determining a delay compensation value according to the average delay error.

In some embodiments, the average delay error may be directly determined as the delay compensation value, that is, the delay compensation value is the average delay error, in this case, when the terminal is at the data sending time, the terminal may predict ephemeris data at the data sending time according to the predicted ephemeris data issued by the nearest satellite base station, then estimate an satellite-to-earth delay value based on the ephemeris data at the data sending time, and then determine the delay compensation value according to the above method, subtract the delay compensation value from the satellite-to-earth delay value, so that the data sending time may be adjusted, that is, the terminal may send data in advance by subtracting the delay compensation value from the satellite-to-earth delay value.

For example, the terminal receives the actual ephemeris data issued by the satellite base station at time t0, and then determines the delay compensation value according to the above methodIf the terminal transmits uplink data at time T1, it can predict and obtain the ephemeris data at time T1 according to the predicted ephemeris data recently issued by the satellite base station, and then predict and obtain the satellite-to-ground delay value T0 at time T1 according to the ephemeris data, which can advance T0Uplink data is transmitted for delay compensation.

On the basis of the first embodiment, the satellite is subject to factors such as earth perturbation, atmospheric resistance, third gravitational force and the like in operation, and the trajectory of the satellite in each satellite orbit operation period has a certain difference, and the longer the time, the larger the trajectory difference between the trajectory and the current time. In order to obtain more historical actual ephemeris data similar to the current actual ephemeris data, the terminal may further store ephemeris data of the satellite base station in a plurality of satellite orbit periods, wherein the satellite orbit period refers to a period of time when the satellite winds the earth for one week. In some embodiments, when the satellite base station transmits the actual ephemeris data and the predicted ephemeris data to the terminal, the corresponding satellite orbit operation period may be marked, for example, after the satellite base station starts up the satellite, the satellite orbit operation period is the first satellite orbit operation period, the ephemeris data transmitted in the satellite orbit operation period may mark the identifier of the first satellite orbit operation period, after the satellite orbit is wound around the earth for one week, the ephemeris data transmitted in the satellite orbit operation period may mark the identifier of the second satellite orbit operation period, so that the terminal may store the received actual ephemeris data and the predicted ephemeris data according to the satellite orbit operation period.

When the historical actual ephemeris data is acquired, the stored actual ephemeris data and predicted ephemeris data of the satellite base station in each satellite orbit operation period in a plurality of satellite orbit operation periods can be acquired, then a plurality of historical actual ephemeris data similar to the current actual ephemeris data are screened out from the actual ephemeris data of each satellite orbit operation period, and the historical predicted ephemeris data with the same time as the plurality of historical actual ephemeris data are acquired from the predicted ephemeris data of the corresponding satellite orbit operation period. The closer the satellite orbit running period is to the current time, the closer the acquired history ephemeris data is to the current time, the smaller the track difference between the satellite running track and the current time is, and the higher the accuracy of the determined time delay compensation value is.

The actual ephemeris data and the predicted ephemeris data of each satellite orbit period in the terminal can be stored independently, so that a plurality of satellite orbit periods with similar time can be selected based on the satellite orbit period in which the current actual ephemeris data is located. For example, the satellite orbit operation period in which the current actual ephemeris data is located is the 5 th satellite orbit operation period, then the historical actual ephemeris data similar to the current actual ephemeris data in the 2 nd satellite orbit operation period-5 th satellite orbit operation period can be obtained, and of course, the historical actual ephemeris data similar to the current actual ephemeris data in all satellite orbit operation periods can also be obtained.

For example, the plurality of satellite orbit operation periods include 3 satellite orbit operation periods, the terminal can firstly read the ephemeris data of each satellite orbit operation period, then find the historical actual ephemeris data similar to the current actual ephemeris data in the ephemeris data corresponding to each satellite orbit operation period, and acquire the corresponding predicted ephemeris data for each screened historical actual ephemeris data, so as to ensure that the time of each screened historical actual ephemeris data is consistent with the time of the corresponding historical predicted ephemeris data. The screened historical actual ephemeris data and corresponding historical predicted ephemeris data are then stored for subsequent calculation of the delay error.

Based on the above embodiment, in the manner of acquiring the historical actual ephemeris data similar to the current actual ephemeris data, a plurality of historical actual ephemeris data having a distance from the current actual ephemeris data smaller than the set threshold may be selected from the actual ephemeris data of each satellite orbit period.

The distance here may refer to a euclidean distance, a cosine distance, or the like, for example, current actual ephemeris data and historical actual ephemeris data may be converted into vectors, and then the euclidean distance or the cosine distance between the two vectors may be calculated.

Or the distance may refer to a distance between positions of satellites included in two ephemeris data, for example, a position coordinate of a satellite is obtained from current actual ephemeris data, a position coordinate of a satellite is obtained from historical actual ephemeris data, a distance between two position coordinates is calculated, the distance may be used to measure similarity of satellite trajectories, and if the distance between two position coordinates is less than a set threshold, the similarity of satellite trajectories is considered to be large.

The set threshold can be flexibly set according to actual requirements, for example, the precision of delay errors is considered, and the set threshold can be set smaller.

On the basis of the above embodiment, in the manner of acquiring the historical actual ephemeris data similar to the current actual ephemeris data, the target actual ephemeris data having the smallest distance to the current actual ephemeris data may be first selected from the actual ephemeris data of each satellite orbit operation period, and then a plurality of historical actual ephemeris data in a set period including the time corresponding to the target actual ephemeris data in each satellite orbit operation period may be acquired.

In each satellite orbit operation period, the target actual ephemeris data with the smallest distance from the current actual ephemeris data is found, and the distance is calculated by referring to the related implementation manner in the above embodiment, which is not repeated here. In this way, for each satellite orbit period, one target actual ephemeris data may be obtained.

For each target actual ephemeris data, a plurality of historical actual ephemeris data for a set period of time including its corresponding time is obtained. For example, for the target actual ephemeris data in the satellite orbit operation period 1, the corresponding time is T1, a plurality of historical actual ephemeris data in a set time period including T1 in the satellite orbit operation period 1 can be obtained, the set time period such as t1+t or T1-T or (T1-T, t1+t) (the value of T can be set according to the requirement and can be a smaller time period such as 5 minutes), then the historical actual ephemeris data in the set time period is searched from the actual ephemeris data corresponding to the satellite orbit operation period 1, and then the historical predicted ephemeris data at the corresponding time is searched from the predicted ephemeris data of the satellite orbit operation period 1.

On the basis of the above embodiment, when calculating the average delay error, the average delay error corresponding to each satellite orbit operation period may be determined according to the delay errors between the plurality of historical actual ephemeris data and the plurality of historical predicted ephemeris data in each satellite orbit operation period.

The calculation formula can be as follows:

wherein, the Representing the average delay error of the j-th satellite orbit period, M represents the number of historical actual ephemeris data corresponding to the satellite orbit period (i.e., the number of historical actual ephemeris data similar to the current actual ephemeris data),The time delay error between the historical actual ephemeris data and the historical predicted ephemeris data at the ith moment in the satellite orbit running period is represented, and the time delay error can be referred to the implementation manner in the related embodiment.

In some embodiments, the average delay errors corresponding to the multiple satellite orbit periods may be re-averaged, and the obtained value may be used as the delay compensation value.

On the basis of the above embodiment, in the manner of determining the delay compensation value according to the average delay error, the delay error corresponding to each satellite orbit period may be determined according to the average delay error corresponding to each satellite orbit period and the delay fluctuation amounts of the delay errors between the plurality of historical actual ephemeris data and the plurality of historical predicted ephemeris data in each satellite orbit period, and then the delay compensation value may be determined according to the delay error corresponding to each satellite orbit period.

The average delay error represents the central tendency of the error, and if the error fluctuates greatly, this risk cannot be captured using the average. The delay error may also be determined here taking into account the delay fluctuation amount. The amount of time delay fluctuation can be used to measure the fluctuation degree of time delay errors between a plurality of historical actual ephemeris data and a plurality of historical predicted ephemeris data, and the larger the amount of time delay fluctuation is, the larger the fluctuation of the errors is, the higher the uncertainty is, the higher the probability of extreme errors is, and the extreme errors can cause negative time delay, so that in order to ensure the reliability of compensation, the fluctuation range of the errors can be considered, and the aim is to construct a conservative and safe compensation boundary so as to ensure that the errors in most cases can be covered.

Therefore, when determining the time delay error of each satellite orbit running period, considering the time delay fluctuation amount can help to determine the magnitude degree of the time delay compensation value, for example, if the time delay fluctuation amount is large, the time delay compensation value needs to consider more error fluctuation, if the time delay fluctuation amount is small, the error is concentrated, and the time delay compensation value can directly depend on the average value.

The time delay fluctuation amount can be represented by a standard deviation or a variance, when the time delay fluctuation amount is calculated, the time delay error between each historical actual ephemeris data and the corresponding historical prediction ephemeris data can be calculated first, then a plurality of time delay errors can be obtained, the corresponding standard deviation or variance is calculated based on the plurality of time delay errors, and the time delay fluctuation amount can be determined according to the standard deviation or variance.

When determining the delay error of each satellite orbit operation period, the average delay error can be added with the delay fluctuation amount to obtain the delay error, such as,Representing the delay error of the j-th satellite orbit period,Representing the average delay error of the j-th satellite orbit period,Representing the amount of delay fluctuation.

In some embodiments, an adjustment parameter k may be further configured to adjust the magnitude of the delay fluctuation amount, so as to balance the average delay error and the influence of the delay fluctuation amount, that is, the delay fluctuation amount may be determined based on a standard deviation of the delay error between the plurality of historical actual ephemeris data and the plurality of historical predicted ephemeris data and k in each satellite orbit period, and may be a product of the standard deviation and k. The time delay error of each satellite orbit running period can be obtained by adopting the following calculation formula:

The standard deviation is indicated as such, =* K. It can be understood that the delay error is a randomly distributed value, the larger the value of k is, the larger the duty ratio of the delay fluctuation amount is, the smaller the probability that the satellite base station receives the negative delay data is, but the larger the value of k is, the CP length in the symbol is wasted, so that the range of the timing delay estimation is reduced, and therefore, through a large number of experiments, the effect is better when the value of k is generally 3, and of course, the delay fluctuation amount is equal to the standard deviation when the value of k is 1. It will be appreciated that the amount of delay variation may also be calculated based on the variance, for example, the product of the variance and a coefficient, which may in particular also be determined by a number of experiments.

In some embodiments, the value of k may also be considered based on several factors:

Factor 1, required confidence level:

Statistically, if the error obeys a normal distribution, k=1 means that the delay error can cover about 68% of the historical error case @ ) K=2 means that about 95% of the cases can be covered @) K=3 means that about 99.7% of the coverage can be achieved). In satellite communications, demodulation failure is costly and therefore a high confidence level is typically required, so k can take on a value of 2 or 3.

Factor 2, characteristics and dynamics of satellite orbit:

Low orbit satellites (LEO) have low orbit height, are greatly influenced by aerodynamic forces such as atmospheric resistance, have high uncertainty of orbit prediction, have large fluctuation of delay errors (sigma, large sigma), and need larger k value to ensure safety.

The medium orbit (MEO) or high orbit (GEO) satellite has relatively stable orbit, small fluctuation of prediction error and proper small k value.

Factor 3, tolerance of the system to negative latency:

if the system design is very fragile, causing serious problems even if a negative delay occurs occasionally, a very large k value is needed to avoid this almost absolutely.

If the system has some fault tolerance (e.g., additional guard intervals) and occasional estimation deviations can be tolerated, the k value can be made smaller in exchange for higher resource utilization (avoiding overcompensation).

Factor 4, obtained based on the test:

In the system test or initial operation stage, a large amount of time delay errors of the historical actual ephemeris data and the historical predicted ephemeris data can be collected, a distribution diagram of the time delay errors is drawn, and whether the distribution diagram is close to normal distribution is checked. A series of different k values are set, historical data is used, each k value is used for simulating the compensation process of the scheme, and the probability of occurrence of a negative delay event under each k value is counted. Then a minimum k value is selected that meets the system target reliability requirements (e.g., the probability of negative delay occurrence is less than 0.1%). Meanwhile, the overcompensation condition under different k values can be observed (namely, the actual time delay after compensation is far smaller than that estimated, so that the resource utilization rate is reduced), and the balance between the reliability and the efficiency is achieved.

After the delay errors corresponding to the satellite orbit running periods are obtained, the delay errors can be averaged again, and the obtained value can be used as a delay compensation value.

On the basis of the above embodiment, in the manner of determining the delay compensation value according to the delay error corresponding to each satellite orbit operation period, the delay error corresponding to each satellite orbit operation period may be weighted and summed to obtain the delay compensation value, where the calculation formula is as follows:

wherein, the Represents the time delay compensation value, N represents the number of satellite orbit operation periods,Representing the weight corresponding to the j-th satellite orbit run period,And the delay error corresponding to the j-th satellite orbit running period is represented.

As for the weights, the determination may be made in the form of an average value, that is, the weights corresponding to the respective satellite orbit operation periods are the same. Of course, the weight corresponding to each satellite orbit running period can be considered based on the similarity between the satellite orbit running period and the current running state, and the larger the similarity is, the larger the reference value of the error on the current compensation is, and the higher the weight is. For example, the more distant the historical satellite orbit running period, the larger the difference between the ephemeris predictive error statistical characteristic and the current scene, the lower the reference value, the lower the weight occupied by the reference value, and the more similar the same satellite is in different orbit turns but the space positions (latitude, longitude, altitude and speed vector) are close to each other, so that the more distant the current ephemeris vector is, the more the historical satellite orbit running period is, the more the error distribution can represent the current error distribution, and the greater the weight is.

Mode 1, temporal similarity:

In principle, the closer to the current moment, the satellite orbit running period is, the more similar to the current orbit dynamics characteristic and the space environment are, and the more relevant the statistical characteristic of the prediction error is, so that the satellite orbit running period with more approximate time can be allocated with more weight, for example, the weight can be allocated in a linear attenuation mode according to the distance of the time.

Mode 2, spatial similarity:

In principle, the error characteristic of the historical track segment which is closest to the current actual ephemeris data in space has the most reference value. If the shortest distance between the current actual ephemeris data and each satellite orbit period (specifically, it may be determined by calculating the distance between the current actual ephemeris data and each of the historical actual ephemeris data in the satellite orbit period) can be obtained, then the weight is inversely proportional to the distance, for example, the weight=1/shortest distance, and the closer the distance, the higher the weight.

Mode 3, data quality and reliability:

The smaller the delay fluctuation amount of the delay error in a certain satellite orbit operation period, the more stable the delay error in the satellite orbit operation period is, and the higher the data reliability is, the larger the weight is.

It can be understood that the weights corresponding to the satellite orbit operation periods should be 1 later, and after the weights corresponding to the satellite orbit operation periods are determined according to the above method, the weights can be normalized and then substituted into the above formula to calculate the delay compensation value.

Example two

In this embodiment, the terminal triggers the determination of the delay compensation value according to the period T.

For example, the terminal receives the actual ephemeris data issued by the satellite base station before the time T, and at the time T, the terminal may acquire the actual ephemeris data received recently, and then determine the delay compensation value according to the method in the first embodiment. Then, the ephemeris data at the data transmission time is predicted based on the predicted ephemeris data issued by the latest received satellite base station, the satellite-ground delay value at the data transmission time is estimated based on the ephemeris data, the delay compensation value is subtracted from the satellite-ground delay value, and the obtained delay value can be used for adjusting the data transmission time, for example, the delay value is advanced to transmit the data. If the terminal transmits data in 0-T, the transmitting time is adjusted according to the satellite-to-ground delay value, and if the terminal transmits data in T-2T, the transmitting time is adjusted according to the delay compensation value obtained at the T time.

In this embodiment, the scheme for determining the delay compensation value may refer to the related implementation manner in the first embodiment, and for brevity of description, a detailed description is not repeated here.

Example III

In this embodiment, the terminal triggers the determination of the delay compensation value according to the TA adjustment amount issued by the satellite base station.

After receiving the actual ephemeris data, the terminal also receives the TA adjustment quantity issued by the satellite base station, and then corrects the TA adjustment quantity according to the time delay compensation value adopted at the last data transmission moment to obtain the corrected TA adjustment quantity.

The satellite base station can send TA adjustment amount to the terminal in the random access process and after the terminal is accessed, and the TA adjustment amount is used for indicating the terminal to adjust the sending time of the uplink data. When the terminal receives the TA adjustment amount issued by the satellite base station, the delay compensation value is determined according to the last received actual ephemeris data, and the method for obtaining the delay compensation value may refer to the related implementation manner in the above embodiment, which is not repeated herein.

Because the TA adjustment amount issued by the satellite base station is the time delay feedback value of the data transmitted by the terminal at the last data transmission time, the TA adjustment amount can be corrected based on the time delay compensation value adopted at the last data transmission time, for example, the corrected TA adjustment amount is the TA adjustment amount minus the time delay compensation value, so that the problem that the terminal excessively transmits the data in advance to generate negative time delay at the satellite receiving position can be avoided. The terminal may then adjust the timing of data transmission according to the corrected TA adjustment, e.g., advance the corrected TA adjustment to transmit data.

For example, the terminal receives actual ephemeris data issued by the satellite base station at time t0, receives TA adjustment amount TA1 issued by the satellite base station at time t1, and determines the delay compensation value based on the actual ephemeris data at time t0By usingTA1 is corrected to obtain TA1', the data transmission time of the terminal is T2, and the data transmission time advance is T _pred (satellite-to-ground delay value predicted at T2)+TA1'. The terminal receives actual ephemeris data at the time t3, receives TA adjustment quantity TA4 at the time t4, and determines a time delay compensation value based on the actual ephemeris data at the time t3At this time also utilizeCorrecting TA4 to obtain TA4', and transmitting data by the terminal at time T5, wherein the data transmission time advance is T _pred (satellite-to-ground delay value predicted at time T5)+TA4'. If the terminal has an uplink transmission time between t3 and t4, TA4 may be based onAnd (5) performing correction.

In the manner of correcting the TA adjustment amount, if the TA adjustment amount is greater than the delay compensation value used at the previous data transmission time, the delay compensation value used at the previous data transmission time is subtracted from the TA adjustment amount to obtain the corrected TA adjustment amount, and if the TA adjustment amount is less than or equal to the delay compensation value used at the previous data transmission time, the TA adjustment amount is set to 0 to obtain the corrected TA adjustment amount.

The TA adjustment is understood to be a time delay calculated by the satellite base station and sent to the terminal, and is used to tell the terminal how much time it can advance to send data, so as to compensate for the basic satellite-to-ground transmission delay, and this value is a positive number and may contain errors.

The delay compensation value is predicted through historical data, the current ephemeris prediction value may overestimate the maximum deviation of the actual delay, and the larger the delay compensation value is, the higher the uncertainty is, and the larger the risk of the original sending strategy of the terminal is.

The purpose of the terminal transmitting the signal is to allow the signal to arrive at the center of the desired reception window of the satellite, and if the signal arrives in advance, it may fall outside the reception window, thereby generating a negative delay, resulting in demodulation failure. If the TA adjustment is too large, the terminal may perform excessive delay compensation, and the probability of generating negative delay is larger, so when the TA adjustment is larger than the delay compensation value, the TA adjustment is subtracted by the delay compensation value, and the amount of excessive advanced transmission can be reduced, so that the delay returns to a safer range.

If the TA adjustment is smaller than or equal to the delay compensation value, it indicates that the satellite-to-earth delay value predicted by the terminal at the last sending time is larger than the ideal satellite-to-earth delay value, if the delay error is not considered, the satellite receives negative delay data, and if the delay error is considered, the TA adjustment=the delay compensation value- (the predicted satellite-to-earth delay value). At this time, a relatively conservative strategy can be adopted, i.e. the TA adjustment amount is directly set to 0, and at this time, the TA adjustment amount issued by the satellite base station is not depended, for example, the sending time of the data can be adjusted according to the satellite-to-ground delay value estimated by the terminal or the satellite-to-ground delay value and the time offset value.

In the implementation process, the delay compensation value adopted at the last data transmission moment is used as a dynamic safety threshold value to intelligently correct the original TA adjustment quantity issued by the base station, the rule can radically stop the phenomenon of excessive compensation, when the TA adjustment quantity is too large, the potential risk is eliminated by subtracting the compensation value, and when the TA adjustment quantity is lower than the safety threshold value, the most conservative zero-setting strategy is adopted to preferentially ensure that the signal does not arrive in advance, thereby reducing the demodulation failure problem caused by negative delay as much as possible.

On the basis of the third embodiment, after the corrected TA adjustment amount is obtained, the data transmission time advance of the terminal may be determined according to the corrected TA adjustment amount, the satellite-to-ground delay value determined based on the predicted ephemeris data at the data transmission time, and the time offset value, and then the data may be transmitted according to the data transmission time advance.

The terminal can predict the predicted ephemeris data at the time of data transmission according to the predicted ephemeris data issued by the satellite base station, estimate a satellite-to-ground delay value based on the predicted ephemeris data and the position of the terminal, determine the delay compensation value according to the mode, and then determine the data transmission time advance.

The data transmission time advance is a value obtained by adding the corrected TA adjustment amount to the star-earth time delay value and subtracting the time delay compensation value. Therefore, the time delay compensation value introduced by ephemeris can be further considered based on the satellite-to-ground time delay value and the corrected TA adjustment quantity, and the sending time of the uplink data of the terminal can be dynamically adjusted.

In the implementation process, the corrected TA adjustment amount, the predicted satellite time delay based on the predicted ephemeris of the data transmission time and the time delay compensation value are cooperatively calculated to finally generate the optimal transmission time advance which is fused with the base station instruction, the local prediction and the history error intelligent evaluation, the mechanism is fused with the real-time measurement of the network, the priori knowledge of the model and the history statistics rule, the decision mechanism of the multi-source information fusion realizes the dynamic fine adjustment of the transmission time, the coarse adjustment instruction and the local prediction information of the base station are fully utilized, and the safety calibration is carried out on the multi-source information fusion through the history error compensation value, so that the adjustment of the transmission time is optimal at the current time and the safest in the statistical sense, thereby maximally ensuring the arrival of signals in an ideal receiving window in a complex dynamic satellite channel and simultaneously reducing the negative delay risk as much as possible.

The manner in which the data transmission time advance is determined will be described with respect to the several embodiments described above, assuming that the satellite-to-ground delay is considered in several schemes(Estimated by the terminal based on the current actual ephemeris data) and a time delay compensation value.

As shown in fig. 3, a schedule of delay compensation values is determined for the terminal in various schemes.

Scheme one (corresponding to embodiment one, the satellite base station does not issue TA, and the triggering condition is the actual ephemeris data received by the terminal), as shown in (a) in fig. 3:

the terminal receives actual ephemeris data issued by the satellite base station at the time t0 and determines a time delay compensation value Predicting ephemeris data at time t1 based on the predicted ephemeris data issued by the previous satellite base station, and then estimating the satellite-to-earth delay value based on the ephemeris data at time t1Data transmission time advance =The terminal transmits the uplink data at time t1, and the time adjustment amount is advanced for transmission. The terminal receives actual ephemeris data issued by the satellite base station at the time t2 and determines a time delay compensation valueThen estimate the satellite-to-ground delay value based on the predicted ephemeris data at time t3Time delay compensation valueData transmission time advance =The terminal transmits the uplink data at time t3, and the time adjustment amount is required to be advanced for transmission.

Therefore, for time t1, the data transmission time advance amount=;

For time t3, its data transmission time advance=。

Scheme two (corresponding to embodiment two, the satellite base station does not issue TA, the trigger condition is period T), as shown in (b) in fig. 3:

when the terminal is at the time T, based on the actual ephemeris data received at the time T0 which is the latest time before the time T, the delay compensation value is estimated Data transmission time advance =(Satellite-ground time delay at time t1 of transmission)The terminal transmits the uplink data at time T1 after time T, and the terminal needs to advance the time adjustment amount to transmit the uplink data.

When the terminal is at the 2T moment, the delay compensation value is estimated based on the actual ephemeris data received at the moment T2 which is the latest moment before the 2T momentData transmission time advance =(Satellite-ground time delay at time t 3)The terminal transmits the uplink data at time T3 after time 2T, and the terminal needs to advance the time adjustment amount to transmit the uplink data.

Therefore, for time t1, the data transmission time advance amount=;

For time t3, its data transmission time advance=。

Scheme three (corresponding to embodiment two, the satellite base station issues TA, the trigger condition is period T):

If the satellite base station synchronously transmits the TA, if the terminal receives actual ephemeris data transmitted by the satellite base station at the time t0, the terminal receives the TA adjustment amount transmitted by the satellite base station at the time t1 The time T1 is greater than the time T, and the terminal estimates a time delay compensation value based on the actual ephemeris data received at the time T0 at the time TFor time t1The terminal may transmit the uplink data at time t2 without correction, the data transmission time advance =(Satellite-ground time delay at time t 2)+The terminal transmits the uplink data at time t2, and the time adjustment amount is required to be advanced for transmission.

During the period from the time T to the time 2T, if a new TA adjustment amount issued by the satellite base station is received, the method is utilizedAnd correcting the same.

Scheme four (corresponding to embodiment three, the satellite base station issues TA, and the triggering condition is that the TA adjustment amount issued by the satellite base station is received), as shown in (c) in fig. 3:

In the first combination scheme, the terminal receives actual ephemeris data issued by the satellite base station at the time t0 and receives TA adjustment quantity issued by the satellite base station at the time t1 At this time, a time delay compensation value is estimated based on the actual ephemeris data received at time t0Since the terminal has no data to be sent before, the terminal can not send the data to the terminalWhen the terminal transmits data at time t2, the data transmission time advance=(Star-earth time delay value at time t 2)+The terminal transmits the uplink data at time t2, and the time adjustment amount is required to be advanced for transmission.

The terminal receives actual ephemeris data issued by the satellite base station at the time t3 and receives TA adjustment quantity issued by the satellite base station at the time t4Then estimate the time delay compensation value based on the actual ephemeris data received at time t3At this time use is made ofFor a pair ofPerforming correction to obtain corrected' When the terminal transmits uplink data at time t5, the data transmission time advance=(Satellite-ground time delay value at time t 5)+The terminal transmits the uplink data at time t5, and the time adjustment amount is required to be advanced for transmission.

It will be appreciated that the above schemes are different in terms of determining the time delay compensation value, but the same is true for the time delay compensation value and the time delay compensation value is determined based on the actual ephemeris data received at the most recent time. Wherein, the first and second schemes do not consider the TA adjustment amount, and if both the TA adjustment amounts are considered, the corrected TA adjustment amount is also considered when determining the data transmission time advance.

Referring to fig. 4 in conjunction with the above embodiment of the method, fig. 4 is a block diagram illustrating a delay compensation value determining apparatus 200 according to an embodiment of the present application, where the apparatus 200 may be a module, a program segment or a code on an electronic device. It should be understood that, in correspondence with the above method embodiments, the apparatus 200 is capable of executing the steps involved in the method embodiments, and specific functions of the apparatus 200 may be referred to in the foregoing description, and detailed descriptions are omitted herein as appropriate to avoid redundancy.

Optionally, the apparatus 200 includes:

a data acquisition module 210, configured to acquire current actual ephemeris data issued by the satellite base station;

A data searching module 220, configured to determine a plurality of historical actual ephemeris data similar to the current actual ephemeris data and a plurality of historical predicted ephemeris data corresponding to the plurality of historical actual ephemeris data, where the plurality of historical actual ephemeris data are the same as the corresponding time instants of the plurality of historical predicted ephemeris data, and the historical predicted ephemeris data are predicted based on the historical actual ephemeris data;

a delay error calculation module 230, configured to calculate an average delay error between the plurality of historical actual ephemeris data and the plurality of historical predicted ephemeris data;

the delay compensation module 240 is configured to determine a delay compensation value according to the average delay error.

Optionally, the data searching module 220 is configured to obtain the stored actual ephemeris data and predicted ephemeris data of the satellite base station in each of the plurality of satellite orbit periods, screen a plurality of historical actual ephemeris data similar to the current actual ephemeris data from the actual ephemeris data of each satellite orbit period, and obtain the historical predicted ephemeris data with the same time as the plurality of historical actual ephemeris data from the predicted ephemeris data of the corresponding satellite orbit period.

Optionally, the data searching module 220 is configured to screen a plurality of historical actual ephemeris data with a distance from the current actual ephemeris data being less than a set threshold from the actual ephemeris data of each satellite orbit period.

Optionally, the data searching module 220 is configured to screen out target actual ephemeris data with a minimum distance from the current actual ephemeris data from the actual ephemeris data of each satellite orbit operation period, and acquire a plurality of historical actual ephemeris data in a set time period including a time corresponding to the target actual ephemeris data in each satellite orbit operation period.

Optionally, the data searching module 220 is configured to determine an average delay error corresponding to each satellite orbit period according to delay errors between the plurality of historical actual ephemeris data and the plurality of historical predicted ephemeris data in each satellite orbit period.

Optionally, the delay compensation module 240 is configured to determine a delay error corresponding to each satellite orbit period according to an average delay error corresponding to each satellite orbit period and a delay fluctuation amount of the delay error between the plurality of historical actual ephemeris data and the plurality of historical predicted ephemeris data in each satellite orbit period, and determine a delay compensation value according to the delay error corresponding to each satellite orbit period.

Optionally, the delay compensation module 240 is configured to perform weighted summation on the delay errors corresponding to each satellite orbit running period to obtain a delay compensation value.

Optionally, the apparatus 200 further includes:

And the TA adjustment module is used for receiving the TA adjustment quantity issued by the satellite base station, and correcting the TA adjustment quantity according to the time delay compensation value adopted at the last data transmission moment to obtain the corrected TA adjustment quantity.

Optionally, the TA adjustment module is configured to subtract the time delay compensation value adopted at the previous data transmission time from the TA adjustment amount if the TA adjustment amount is greater than the time delay compensation value adopted at the previous data transmission time to obtain a corrected TA adjustment amount, and set the TA adjustment amount to 0 if the TA adjustment amount is less than or equal to the time delay compensation value adopted at the previous data transmission time to obtain the corrected TA adjustment amount.

Optionally, the TA adjustment module is further configured to determine a data transmission time advance of the terminal according to the corrected TA adjustment amount, a satellite-to-ground delay value determined based on predicted ephemeris data at the data transmission time, and the delay compensation value, and transmit data according to the data transmission time advance.

It should be noted that, for convenience and brevity, a person skilled in the art will clearly understand that, for the specific working procedure of the apparatus described above, reference may be made to the corresponding procedure in the foregoing method embodiment, and the description will not be repeated here.

Referring to fig. 5, fig. 5 is a schematic structural diagram of an electronic device for performing a delay compensation value determining method according to an embodiment of the present application, where the electronic device may include at least one processor 310, such as a CPU, at least one communication interface 320, at least one memory 330 and at least one communication bus 340. Wherein the communication bus 340 is used to enable connected communication between these components. The communication interface 320 of the device in the embodiment of the present application is used for performing signaling or data communication with other node devices. The memory 330 may be a high-speed RAM memory or a nonvolatile memory (non-volatile memory), such as at least one disk memory. Memory 330 may also optionally be at least one storage device located remotely from the aforementioned processor. Stored in memory 330 are computer readable instructions which, when executed by the processor 310, perform the method processes described above.

As an implementation manner, the electronic device may be a terminal, and different terminals may be connected to each other by a wired or wireless manner. The terminal may be widely applied to various scenarios, such as Near Field Communication (NFC) Device-to-Device (D2D), vehicle-to-Device (Vehicle to Everything, V2X) communication, machine-type communication (MTC), internet of things (Interne to Things, IOT), virtual reality, augmented reality, industrial control, autopilot, telemedicine, smart grid, smart furniture, smart office, smart wear, smart transportation, smart city, and the like.

The terminal may also include an antenna and a transceiver. The transceiver conditions (e.g., analog converts, filters, amplifies, and upconverts, etc.) the output samples and generates an uplink signal, which is transmitted via an antenna to the network device, and on the downlink, the antenna receives the downlink signal transmitted by the network device, and the transceiver conditions (e.g., filters, amplifies, downconverts, digitizes, etc.) the received signal from the antenna and provides input samples. The processor 310 is configured to perform the delay correction method described in the above embodiment. The embodiment of the application does not limit the specific technology and the specific equipment form adopted by the terminal.

It will be appreciated that the configuration shown in fig. 5 is merely illustrative, and that the electronic device may also include more or fewer components than shown in fig. 5, or have a different configuration than shown in fig. 5. The components shown in fig. 5 may be implemented in hardware, software, or a combination thereof.

An embodiment of the present application provides a computer readable storage medium having stored thereon a computer program which, when executed by a processor, performs a method procedure performed by an electronic device in the above method embodiment.

The present embodiment discloses a computer program product comprising a computer program stored on a non-transitory computer readable storage medium, the computer program comprising program instructions which, when executed by a computer, are capable of performing the methods provided by the above-described method embodiments, for example, comprising:

Acquiring current actual ephemeris data issued by a satellite base station;

In summary, the embodiments of the present application provide a method, apparatus, device, storage medium and program product for determining a delay compensation value, which effectively overcomes the problem of inaccurate delay estimation caused by model errors and orbit perturbation in the conventional static ephemeris prediction method by introducing a dynamic error compensation mechanism driven by historical ephemeris data, and can more accurately estimate delay deviation at the current moment by calculating historical average delay errors similar to the current scene, thereby significantly reducing the risk of negative delay caused by overcompensation, and improving the transmission reliability of a satellite uplink and the demodulation success rate of a receiver.

In the embodiments provided in the present application, it should be understood that the disclosed apparatus and method may be implemented in other manners. The above-described apparatus embodiments are merely illustrative, for example, the division of the units is merely a logical function division, and there may be other manners of division in actual implementation, and for example, multiple units or components may be combined or integrated into another system, or some features may be omitted, or not performed. Alternatively, the coupling or direct coupling or communication connection shown or discussed with each other may be through some communication interface, device or unit indirect coupling or communication connection, which may be in electrical, mechanical or other form.

Further, the units described as separate units may or may not be physically separate, and units displayed as units may or may not be physical units, may be located in one place, or may be distributed over a plurality of network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

Furthermore, functional modules in various embodiments of the present application may be integrated together to form a single portion, or each module may exist alone, or two or more modules may be integrated to form a single portion.

In this document, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions.

The above description is only an example of the present application and is not intended to limit the scope of the present application, and various modifications and variations will be apparent to those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A method for determining a delay compensation value, characterized in that it is applied to a terminal, the method comprising:

Obtain the current actual ephemeris data sent by the satellite base station;

Determining a plurality of historical actual ephemeris data similar to the current actual ephemeris data and a plurality of historical predicted ephemeris data corresponding to the plurality of historical actual ephemeris data, wherein the plurality of historical actual ephemeris data and the plurality of historical predicted ephemeris data correspond to the same time, and the historical predicted ephemeris data are predicted based on the historical actual ephemeris data;

Calculating an average time delay error between the plurality of historical actual ephemeris data and the plurality of historical predicted ephemeris data;

A delay compensation value is determined according to the average delay error.

2. The method according to claim 1, wherein determining a plurality of historical actual ephemeris data similar to the current actual ephemeris data and a plurality of historical predicted ephemeris data corresponding to the plurality of historical actual ephemeris data comprises:

Acquiring stored actual ephemeris data and predicted ephemeris data of the satellite base station for each satellite orbit operation cycle in a plurality of satellite orbit operation cycles;

A plurality of historical actual ephemeris data similar to the current actual ephemeris data are screened out from the actual ephemeris data of each satellite orbital operation cycle, and historical predicted ephemeris data having the same time as the plurality of historical actual ephemeris data are obtained from the predicted ephemeris data of the corresponding satellite orbital operation cycle.

3. The method according to claim 2, wherein the step of selecting a plurality of historical actual ephemeris data similar to the current actual ephemeris data from the actual ephemeris data of each satellite orbital operation cycle comprises:

A plurality of historical actual ephemeris data whose distances from the current actual ephemeris data are less than a set threshold are screened out from the actual ephemeris data of each satellite orbit operation cycle.

4. The method according to claim 2, wherein the step of selecting a plurality of historical actual ephemeris data similar to the current actual ephemeris data from the actual ephemeris data of each satellite orbital operation cycle comprises:

Filtering out target actual ephemeris data having the smallest distance from the current actual ephemeris data from the actual ephemeris data of each satellite orbit operation cycle;

A plurality of historical actual ephemeris data within a set time period including a time corresponding to the target actual ephemeris data in each satellite orbit operation cycle is obtained.

5. The method according to claim 2, wherein calculating the average time delay error between the plurality of historical actual ephemeris data and the plurality of historical predicted ephemeris data comprises:

The average time delay error corresponding to each satellite orbit operation cycle is determined based on the time delay errors between multiple historical actual ephemeris data and multiple historical predicted ephemeris data within each satellite orbit operation cycle.

6. The method according to claim 5, wherein determining the delay compensation value according to the average delay error comprises:

Determine the delay error corresponding to each satellite orbital operation cycle based on the average delay error corresponding to each satellite orbital operation cycle and the delay fluctuation amount of the delay error between multiple historical actual ephemeris data and multiple historical predicted ephemeris data within each satellite orbital operation cycle;

The delay compensation value is determined according to the delay error corresponding to each satellite orbit operation cycle.

7. The method according to claim 6, wherein the delay fluctuation is determined based on a standard deviation of delay errors between a plurality of historical actual ephemeris data and a plurality of historical predicted ephemeris data within each satellite orbit operation cycle and an adjustment coefficient k.

8. The method according to claim 6, wherein determining the delay compensation value according to the delay error corresponding to each satellite orbital operation period comprises:

The delay errors corresponding to each satellite orbital operation period are weighted and summed to obtain the delay compensation value.

9. The method according to any one of claims 1 to 8, characterized in that after determining the delay compensation value according to the average delay error, the method further comprises:

receiving a TA adjustment value sent by the satellite base station;

The TA adjustment amount is corrected according to the delay compensation value used at the last data sending moment to obtain a corrected TA adjustment amount.

10. The method according to claim 9, wherein the step of correcting the TA adjustment value according to the delay compensation value used at the last data transmission moment to obtain the corrected TA adjustment value comprises:

If the TA adjustment amount is greater than the delay compensation value used at the last data sending moment, subtracting the delay compensation value used at the last data sending moment from the TA adjustment amount to obtain a corrected TA adjustment amount;

If the TA adjustment amount is less than or equal to the delay compensation value used at the last data sending moment, the TA adjustment amount is set to 0 to obtain a corrected TA adjustment amount.

11. The method according to claim 9, characterized in that after obtaining the corrected TA adjustment value, the method further comprises:

Determining a data transmission timing advance of the terminal according to the corrected TA adjustment amount, a satellite-to-ground delay value determined based on predicted ephemeris data at the data transmission time, and the delay compensation value;

The data is sent according to the data sending time advance.

12. A device for determining a delay compensation value, characterized in that it is applied to a terminal, the device comprising:

The data acquisition module is used to obtain the current actual ephemeris data sent by the satellite base station;

a data search module, configured to determine a plurality of historical actual ephemeris data similar to the current actual ephemeris data and a plurality of historical predicted ephemeris data corresponding to the plurality of historical actual ephemeris data, wherein the plurality of historical actual ephemeris data and the plurality of historical predicted ephemeris data correspond to the same time, and the historical predicted ephemeris data are predicted based on the historical actual ephemeris data;

A time delay error calculation module, configured to calculate an average time delay error between the plurality of historical actual ephemeris data and the plurality of historical predicted ephemeris data;

The delay compensation module is configured to determine a delay compensation value according to the average delay error.

13. An electronic device, comprising a processor and a memory, wherein the memory stores computer-readable instructions, and when the computer-readable instructions are executed by the processor, the method according to any one of claims 1 to 11 is executed.

14. A computer-readable storage medium having a computer program stored thereon, wherein when the computer program is executed by a processor, the method according to any one of claims 1 to 11 is executed.

15. A computer program product, comprising computer program instructions, wherein when the computer program instructions are read and executed by a processor, the method according to any one of claims 1 to 11 is executed.